Oh Socks, it is so difficult and yes, so very upsetting.
I did mention my Lab was on the same meds, he had arthritis and then his cruciate ligament gave way. He was 11 and we felt he was too old to recover from the surgery and still have to deal with the arthritis.
We had him on the meds for a while , but it wasn't long after that he then couldn't control his bladder and for some reason his teeth started to fall out.
So we decided it was time. But I still get tearful now, years later. It was the hardest decision ever, not helped by the fact my ex had just moved out and Ddog was my son's dog. He was 14 then.
But we kept him home for another week, spoilt him rotten (he was on a diet practically his whole life, because Labrador), and took every moment we could to let him know how much he was loved. He wasnt very mobile so he laid on a sleeping bag and we pulled him around everywhere. He ate rump steak, had a new collar (he just loved having a new collar), and all the attention we could give him. We took so many photos.
I knew it couldn't be more than that time wise as he was on so many meds for pain, I sometimes feel bad that that week was for us rather than him.
We kept his ashes and he is here with me. I say hello to him every day and sometimes I just sit and chat to him.
I really do know how difficult this is. So although I am a complete stranger to you, you are in my thoughts. I know it's not straightforward or an easy decision. but I also know it's also not easy to see our furry family being unhappy.
Let's hope the vet has some answers for you, maybe the meds are just not the right ones.
💐